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Influence of interlayer tunneling on the quantized Hall phases in intentionally disordered multilayer structures
Yu A Pusep1, A Rodriguez, A H Arakaki
1Instituto de Fisica de São Carlos, Universidade de São Paulo, 13460-970 São Carlos, SP, Brazil.
Summary
Interlayer disorder in quantum Hall phases can disrupt quantization, leading to the breakdown of the quantum Hall effect. Dimensionality differences between metallic and insulating phases were observed, with transition widths linked to electron density fluctuations.
Area of Science:
- Condensed matter physics
- Quantum Hall effect studies
Background:
- The stability of quantized Hall phases is crucial for understanding electronic behavior in layered materials.
- Interlayer correlations significantly influence quantum phenomena in multilayer systems.
Purpose of the Study:
- To investigate the stability of quantized Hall phases in weakly coupled multilayers.
- To determine the impact of interlayer correlations, tunneling, and disorder on the quantum Hall effect.
Main Methods:
- Studying weakly coupled multilayers with controlled interlayer correlations.
- Analyzing the effects of interlayer tunneling and random variations in well thicknesses.
- Investigating the dimensionalities of metallic and insulating quantum Hall phases.
Main Results:
- Strong interlayer disorder was found to destroy the symmetry responsible for Hall conductivity quantization, causing quantum Hall effect breakdown.
- A distinct difference in dimensionality between metallic and insulating quantum Hall phases was demonstrated.
- The sharpness of quantized Hall steps correlated with calculated interlayer tunneling energies.
- The transition width between quantized Hall states in disordered multilayers was explained by local electron density fluctuations.
Conclusions:
- Interlayer disorder is a critical factor in the stability and breakdown of quantum Hall phases.
- The dimensionality of quantum Hall phases is dependent on the degree of interlayer coupling and disorder.
- Electron density fluctuations play a key role in the observed transition dynamics in disordered systems.
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